Immunology Flashcards
what do primary immunodeficiencies often present with?
recurrent respiratory tract infections
what do primary antibody deficiencies often present with?
sinusitis
otitis media
four examples of primary antibody deficiencies
- selective IgA deficiency
- common variable immunodeficiency (CVID)
- specific antibody deficiency (SAD)
- X-linked agammaglobulinemia (XLA)
what do complement disorders often present with
laryngeal angioedema
three stages where development of neutrophils can go wrong
- defects in development
- defects in trans-endothelial migration
- defects in neutrophil killing
example of a condition that results in defects in neutrophil development
severe congenital neutropenia (Kostmann syndrome)
how can severe congenital neutropenia (Kostmann syndrome) be detected
accumulation of precursor cells in the bone marrow
example of a condition that results in defects in neutrophil transendothelial migration
leukocyte adhesion deficiency
example of a condition that result in defects in neutrophil killing
chronic granulomatous disease (CGD)
what does CGD cause?
inability to generate ROS/RNS
management for conditions with defects in neutrophil production
- immunoglobulin replacement therapy
- management of infection
- stem cell transplantation
- gene therapy
therapy for CGD
IFN-gamma therapy
which bacterial species can hide within immune cells?
mycobacteria species
what is the defence network against mycobacteria species called?
IL-12 IFN-gamma network
describe the IL-12 IFN-gamma network
- infected macrophages produce IL-12
- this stimulates NK cells and TH1 to secrete IFN-gamma
- this stimulates macrophages to activate NADPH oxidase complex
five stages where adaptive immune system production can go wrong?
- defects in haemopoietic stem cells
- defects in lymphoid precursor cells
- defects in thymocyte development
- defects in B cell development
- defects in B cell effector functions
example of a condition which results in defects in haemopoietic stem cells
reticular dysgenesis (fatal unless HSC transplantation)
example of a condition which results in defects in lymphoid precursor cells
severe combined immunodeficiencies (SCID)- both T and B cells are not produced. commonest form is X-linked SCID
example of a condition that results in defects in thymocyte development
DiGeorge syndrome
example of a condition that results in defects in B cell development
X-linked agammaglobulinaemia (XLA)
two conditions that result in defects in B cell effector functions
hyper IgM syndrome
selective IgA deficiency
define hypersensitivity reaction
abnormal immune response that results in bystander damage to self
how are hypersensitivity reactions divided?
Gel and Coomb’s classification
type 1 hypersensitivity reaction
immediate hypersensitivity where IgE antibody response to an external antigen.
for type 1 hypersensitivity what happens when an atopic individual comes into contact with an allergen
TH2 response (as well as TH1) which produces mast cells and eosinophils which express Fc receptors for the antibody and when the allergen binds it disrupts the IgE membrane releasing histamine
example of type 1 hypersensitivity reaction
allergic reaction
management of type 1 hypersensitivity reaction
avoid allergen
block mast cells
anti-inflammatory agents
immunotherapy
what is a type 2 hypersensitivity reaction?
direct cell effects: IgM or IgG antibodies attack the cell surface (autoantibodies)
example of a type 2 hypersensitivity reaction
Goodpasture’s syndrome
goodpastures syndrome
IgM or IgG attack the basement membrane of cells in the lungs and kidneys
management of good pastures syndrome
- corticosteroids
- plasmapheresis
- stop smoking
type 3 hypersensitivity reaction
immune complex mediated: immune complexes are deposited in blood vessel walls where their presence initiates inflammatory cells (neutrophil releases enzyme that damage the basement membrane)
example of a type 3 hypersensitivity reaction
hypersensitivity pneumonitis
management of pneumonitis
avoidance
corticosteroids
immunosuppression
type 4 hypersensitivity reaction
delayed type hypersensitivity
examples of type 4
TB
sarcoidosis
what happens in type 4
inhalation of antigen results it activation of immune cells leading to granuloma formation which causes tissue damage and fibrosis
management of type 4
NSAIDS
corticosteroids
